1. Field of the Invention
The present invention relates in general to radiation shields, and more particularly to a shield which converts radiation into ionic movement to dissipate same. Such a shield is suitable for use with devices that emit radiation, for example, a cellular telephone which emits radiation from an antenna.
2. Background Art
Cellular telephones, and other devices, such as wireless devices, that communicate through the airwaves, transmit undesirable radiation when in use. While the relative quantity of radiation that is transmitted is not of great magnitude, repetitive use of such devices, especially in close proximity to the human body (i.e. a cellular telephone proximate the ear of the user), has been shown to impart relatively high levels of radiation which permeate the body of the user, and more particularly the head of the user. Such high levels of exposure have certain experts believing that the devices are relatively dangerous and may be a health risk.
One solution, designed to limit the quantity of radiation received by a user, has involved the use of separate microphone and speaker in the form of an earpiece. While this has limited the radiation emitted to the user, it is not without drawbacks. First, such a separate component adds complexity to the cellular telephone in the form of cords and plugs (which can become tangled and disconnect from the phone). Moreover, certain users are not comfortable with the use of earphones and microphones, and prefer the customary and conventional use of a telephone headset.
The invention comprises a radiation shield for use with a device that emits radiation. The shield comprises a barrier positioned between a source of radiation and an object to be shielded. The barrier includes means for converting radiation into ionic motion. In turn, the ionic motion dissipates the radiation and substantially precludes the radiation from reaching an object to be shielded.
In a preferred embodiment, the radiation converting means comprises an ionic conducting material positioned between the source of radiation and an object to be shielded. In one such embodiment, the ionic conducting material comprises a membrane supported by a frame. In one embodiment, the membrane is selected from the group consisting of one or more of: hydrated compounds, Nafion family materials, Nasicons, xcex2 Alumina, xcex2xe2x80x3 Alumina, chalcogenides, halides, oxides, solid polymer electrolytes, aqueous salt solutions and gels, as well as mixtures thereof. Preferably, the ionic conductor includes a conductivity of at least 10xe2x88x928 siemens/cm at ambient temperature.
In another preferred embodiment, the barrier further includes means for removing heat from the radiation converting means. In one such embodiment, the heat removing means comprises a heat sink associated with the radiation converting means. In a particular such embodiment, the heat sink comprises a metal, a ceramic and/or a polymer substrate. Preferably, the heat sink may comprise one of the group consisting of aluminum, graphite, magnesia and steel, as well as mixtures and alloys thereof.
In another aspect of the invention, the invention comprises the radiation shield identified above used in combination with a device having an antenna capable of emitting radiation. In such an embodiment, the barrier including means for converting radiation imparted by the antenna to toward a user, into ionic motion.
In one such embodiment, the invention further comprises means for slidably positioning the barrier relative to an antenna. In another such embodiment, the invention includes means for pivoting the barrier relative to an antenna.
The invention further comprises a method of precluding damage to a user from radiation emitted by an antenna of a device. The method comprises the steps of providing a barrier having means for converting radiation into ionic motion and positioning the barrier between a radiation emitting antenna of the device and a body surface of a human, to, in turn, facilitate receipt of radiation by the barrier.
In a preferred embodiment, the method further comprises the step of adjusting the barrier relative to the antenna or relative to the device to maximize receipt of radiation by the barrier. In one such embodiment, the step of adjusting further comprises the step of pivotally rotating the barrier relative to the antenna or the device. In another such embodiment, the step of adjusting further comprises the step of slidably moving the barrier relative to the antenna or device.
In another embodiment of the method, the method further comprises the step of associating a heat sink with the barrier to, in turn, dissipate heat from the barrier.
The invention further comprises a method of dissipating radiation emitted by a device, such as a cellular telephone. This method comprises the steps of emitting radiation from an antenna of the device; receiving radiation into a barrier; and converting the radiation into ionic motion within the barrier.
In one preferred embodiment, the method further includes the step of dissipating the heat generated within the barrier.
In another preferred embodiment, the method further comprises the step of adjusting the barrier relative to the antenna to maximize the receipt of radiation by the barrier.